Can pulling out prevent pregnency

If done perfectly it can prevent pregnancy. However this requires the male to pull out just *before* he ejaculates and ensure none of his sperm are released in or near the vagina. With "perfect use" the failure rate is 4% per year.

This is very difficult and unlikely to succeed as it requires concentration and self-control at a point when it is very difficult to concentrate on it. Thus the actual failure rate is 15-28% per year. This means that for every 100,000 couples that use this method, 15,000-28,000 get pregnant.

It is a poor choice of methods because it depends on the male to remember to pull out in time. I would personally strongly suggest using the pill, or condoms, or a diaphram, or better yet, a combination of methods.